In one aspect, the present invention relates to a furnace having a heated portion arranged adjacent to an unheated portion. A plurality of straight tubes are formed of a first material and are at least partially disposed in the heated portion. A plurality of return bends are operatively coupled to the plurality of straight tubes. The plurality of return bends are formed of a second material and are at least partially disposed in the unheated portion. The first material exhibits a maximum temperature greater than the second material thereby facilitating increased run time of the furnace. The second material exhibits wear-resistance properties greater than the first material thereby facilitating wear-resistance of the furnace.

In one aspect, the present invention relates to a furnace having a heated portion arranged adjacent to an unheated portion. A plurality of straight tubes are formed of a first material and are at least partially disposed in the heated portion. A plurality of return bends are operatively coupled to the plurality of straight tubes. The plurality of return bends are formed of a second material and are at least partially disposed in the unheated portion. The first material exhibits a maximum temperature greater than the second material thereby facilitating increased run time of the furnace. The second material exhibits wear-resistance properties greater than the first material thereby facilitating wear-resistance of the furnace.

A coke oven may comprise an upper oven and a lower oven beneath the upper oven. Crude gas produced in a coking chamber of the upper oven during a coking process is incompletely combusted in the upper oven and may subsequently be conducted into the lower oven via downwardly directed downcomer channels. The crude gas may flow through an outer sole flue, may be deflected in a transition region, may flow through an inner sole flue, and may exit the lower oven via an exhaust gas collecting channel. The outer and inner sole flues may be supplied with secondary air such that the gas initially partially combusted in the upper oven by means of primary combustion is completely combusted in the lower oven by means of secondary combustion. The transition region in which the gas is deflected in the lower oven may be divided into a plurality of flow channels.

A coke oven may comprise an upper oven and a lower oven beneath the upper oven. Crude gas produced in a coking chamber of the upper oven during a coking process is incompletely combusted in the upper oven and may subsequently be conducted into the lower oven via downwardly directed downcomer channels. The crude gas may flow through an outer sole flue, may be deflected in a transition region, may flow through an inner sole flue, and may exit the lower oven via an exhaust gas collecting channel. The outer and inner sole flues may be supplied with secondary air such that the gas initially partially combusted in the upper oven by means of primary combustion is completely combusted in the lower oven by means of secondary combustion. The transition region in which the gas is deflected in the lower oven may be divided into a plurality of flow channels.

A process for the thermal-chemical modification treatment of wood is described, in which such a modification is obtained through multiple chemical reactions of the substances comprising the wood structure generated by exposing the wood to temperatures at which the pyrolysis phenomenon begins, i.e., in the range of 180 C.-240 C., in a vacuum autoclave-cell while always maintaining the internal pressure lower than the atmospheric pressure, in a range of values of 70-350 mBar of absolute pressure, consisting in the steps of pre-heating, actual heat treatment, and cooling of a wood mass.

A process for the thermal-chemical modification treatment of wood is described, in which such a modification is obtained through multiple chemical reactions of the substances comprising the wood structure generated by exposing the wood to temperatures at which the pyrolysis phenomenon begins, i.e., in the range of 180 C.-240 C., in a vacuum autoclave-cell while always maintaining the internal pressure lower than the atmospheric pressure, in a range of values of 70-350 mBar of absolute pressure, consisting in the steps of pre-heating, actual heat treatment, and cooling of a wood mass.

Coke oven corbel structures include an assembly of multiple stacked tiers of refractory blocks defining a plurality of substantially vertically oriented central flues and a plurality of diagonally oriented lateral flues. At least one tier of refractory blocks in the assembly includes a plurality of tongue-and-groove interconnected refractory blocks. This plurality of interconnected refractory blocks of the at least one tier comprise mutually substantially orthogonal faces defining an edge and respectively including an elongate tongue protruding outwardly therefrom and an elongate groove recessed therein. The elongate tongue and groove include respective adjacent ends which co-terminate with one another at the edge defined by the mutually orthogonal faces of the refractory blocks.

Coke oven corbel structures include an assembly of multiple stacked tiers of refractory blocks defining a plurality of substantially vertically oriented central flues and a plurality of diagonally oriented lateral flues. At least one tier of refractory blocks in the assembly includes a plurality of tongue-and-groove interconnected refractory blocks. This plurality of interconnected refractory blocks of the at least one tier comprise mutually substantially orthogonal faces defining an edge and respectively including an elongate tongue protruding outwardly therefrom and an elongate groove recessed therein. The elongate tongue and groove include respective adjacent ends which co-terminate with one another at the edge defined by the mutually orthogonal faces of the refractory blocks.

In one aspect, the present invention relates to a furnace having a heated portion arranged adjacent to an unheated portion. A plurality of straight tubes are formed of a first material and are at least partially disposed in the heated portion. A plurality of return bends are operatively coupled to the plurality of straight tubes. The plurality of return bends are formed of a second material and are at least partially disposed in the unheated portion. The first material exhibits a maximum temperature greater than the second material thereby facilitating increased run time of the furnace. The second material exhibits wear-resistance properties greater than the first material thereby facilitating wear-resistance of the furnace.

In one aspect, the present invention relates to a furnace having a heated portion arranged adjacent to an unheated portion. A plurality of straight tubes are formed of a first material and are at least partially disposed in the heated portion. A plurality of return bends are operatively coupled to the plurality of straight tubes. The plurality of return bends are formed of a second material and are at least partially disposed in the unheated portion. The first material exhibits a maximum temperature greater than the second material thereby facilitating increased run time of the furnace. The second material exhibits wear-resistance properties greater than the first material thereby facilitating wear-resistance of the furnace.